• 제목/요약/키워드: buffering effects

검색결과 125건 처리시간 0.024초

섬유소 공급원이 면양의 반추위 pH, Buffering Capacity 및 소화율에 미치는 영향 (Effects of Fiber Sources on Ruminal pH, Buffering Capacity and Digestibility in Sheep)

  • 서인준;김명화;김동식;이상락;맹원재
    • 한국초지조사료학회지
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    • 제25권3호
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    • pp.177-184
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    • 2005
  • 본 연구는 섬유소공급원 7종, alfalfa hay cube (AHC), corn cob (CC), corn silage (CS), cotton seed hull (CSH), peanut hull (PHL), rice straw(RS), sugar cane bagasse(SCB)의 반추위에서의 반추활동, pH, 완충능력과 전소화기관 내 소화율을 알아보고자 실시하였다. 공시 동물은 평균체중 37.1kg인 Corridale종 수 면양 5두 (3두는 반추위 fistula 부착)를 사용하였으며, 실험기간동안 공시동물에게 급여한 사료는 각각의 조사료원 $45\%$와 corn-based 사료 $55\%$의 비율로 하여 1일 2회 (09:00, 21:00) 총 800g(dry matter basis)을 급여하였다. Ruminal pH는 급여 후 4시간까지는 처리구 간에 차이가 없었지만 8시간 후 타 조사료원$(6.24\~6.61)$과 RS(5.78)간에는 차이가 있었다(p<0.05). 반추위 내 완충능력은 SCB구, CC구와 비교하여 CS구에서 사료급여 후 0시간(p<0.05), 2시간(p<0.05)에 유의한 차이를 나타내었고, 사료급여 후 12시간 경과 시 AHC구를 제외한 CC구, CS구, SCB구와 RS구 보다 PHL구(p<0.01)에서 높게 나타났다. DM 소화율은 CS구에서 $78.19\%$로 타처리보다 유의하게 높았으며(p<0.05), DNF 소화율은 CC구, CS구, CSH구와 RS구가 다른 조사료원 급여구보다 높게 나타났다. (p<0.001).

우울감과 자살위험간의 관계에서 가족결속도의 완충효과 (The Buffering Effect of Family Cohesion in the Relationship between Depression and Suicidal Risk)

  • 김윤정;강현정
    • 한국콘텐츠학회논문지
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    • 제14권3호
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    • pp.241-249
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    • 2014
  • 본 논문은 청소년, 성인, 노인의 우울과 자살위험간의 관계에서 가족결속도의 완충효과를 파악하는데 연구 목적이 있다. 이를 위해 2010년 5월부터 8월 사이에 청소년 399명, 성인 473명, 노인 370명을 대상으로 전국 10개 도시에서 설문조사를 하였다. 주요 연구결과를 살펴보면, 첫째, 자살위험과 우울감 수준은 노인이 가장 높고, 청소년, 성인 순이었으나, 가족결속력은 성인이 가장 높고, 노인, 청소년 순이었다. 둘째, 우울과 자살위험간의 관계에서 가족결속도의 완충효과를 분석한 결과 청소년과 성인의 경우에만 유의미한 결과가 나타났다, 즉, 청소년과 성인의 가족결속도는 우울감이 자살위험에 미치는 영향을 완화시키는 것으로 나타났다. 이는 청소년과 성인의 자살감소를 위해서 가족결속력을 향상시켜야 함을 제시하는 결과이다. 그러나 가족관계가 어느 시기보다 중요한 노인의 경우 우울과 자살생각간의 관계에서 가족결속도의 완충효과가 검증되지 않았다. 이에 대한 해석을 노년기 자살의 특성에서 논의하였다.

SBR에서 충격부하에 따른 완충효과 (Buffering effects of shock loads in sequencing batch reactor)

  • 지대현;이광호;이재근
    • 상하수도학회지
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    • 제22권5호
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    • pp.581-587
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    • 2008
  • In this study, we investigated the buffering effect with different COD, $NH_4{^+}-N$ and TP shock loads on the performance of lab-scale Sequencing Batch Reactor(SBR) using synthetic wastewater. This study was operated under the following conditions : HRT, 12 hrs : MLSS, 2,000 mg/L : F/M ratio, $0.2kgCOD/kgMLSS{\cdot}d$ : SRT, 20days, and was increased by a factor, COD : ranging from 200-2000 mg/L, $NH_4{^+}-N$ : ranging from 30-300 mg/L, T-P : ranging from 5-50 mg/L in the reactor. As results, COD removal rate at different shock loads was decreased until 42.1%(stable state : 95%) and concentration with effluent was higher than 695 mg/L(at Run 6). In case of $NH_4{^+}-N$ removal rate was decreased until 35.8% from 97.0% and also T-P removal rate was decreased until 5.0%. Effluent concentrations of COD, $NH_4{^+}-N$ and T-P were rapidly increased according to shock loads and needed 3, 4 and 6 additional cycle times for recovering the stable condition.

한부모가족의 적응 - 가족탄력성의 완충효과 (Adjustment of Single Parent Family - The Buffering Effect of Family Resilience)

  • 현은민
    • 가정과삶의질연구
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    • 제25권5호
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    • pp.107-126
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    • 2007
  • This study explored the buffering effect of family resilience between family stress and adjustment of single parent family based on family resilience approach. Results of the study were as followed: First, single parents who had a lower level of family stress and a higher lever of family resilience reported a higher level of family adjustment. Second, family stress especially economic stress and relational stress influenced negatively on adjustment of single parent family. Family belief system, organizational pattern and communication processes of the three sub-factors of family resilience influenced positively on family adjustment. However the sub-factors of family resilience had more powerful effects than family stress. Third, family belief system, organizational pattern and communication processes of the three sub-factors of family resilience had a moderating effect between family adjustment and psychological stress and between family adjustment and relational stress. Especially the three sub-factors of family resilience had a buffering effect between family adjustment and relational stress. The results of this study had important implication for theory, research, and practice. The study showed that adjustment of single parent family could be significantly explained by family resilience rather than family stress. Accordingly strength perspective-based intervention focused on family resilience would be more effective than deficit perspective-based intervention based on family stress.

숲의 종류에 따른 생리적 치유효과 분석 - 고혈압과 당뇨병 환자를 중심으로 - (Analysis of the Physiological Healing Effects by Forest Types - Focused on Hypertensive and Diabetic -)

  • 정나라;안득수
    • 한국조경학회지
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    • 제43권5호
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    • pp.1-12
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    • 2015
  • 본 연구는 숲의 종류에 따른 이용자의 생리적 효과를 분석하기 위하여 실시하였다. 숲은 편백나무숲, 졸참나무숲, 소나무 숲으로 구분하고, 실험대상 집단은 고혈압 환자(64명), 당뇨병 환자(59명) 및 일반인(59명)으로 구분하여 생리적 반응을 측정하였다. 생리적 반응은 뇌파, 심박 변이, 혈압, 맥박, 코티졸, 혈압 등을 지표로 선정하였다. 전체 피험자의 생리적 반응으로 숲의 스트레스 완화효과를 분석한 결과, 졸참나무숲은 중추신경계, 자율신경계, 내분비계 측면에서 다른 숲에 비하여 높은 스트레스 완화효과를 기대할 수 있다. 편백나무숲은 자율신경계를 제외한 지표에서, 소나무숲은 내분비계와 자율신경계 일부 지표에서 스트레스 완화에 기여할 수 있다. 그러나 소나무숲은 스트레스 완화효과에 있어서 상대적으로 효과가 적다. 고혈압 환자는 효과의 정도 측면에서 소나무숲보다 편백나무숲과 졸참나무숲에서 체류할 때 높은 혈압 강하의 효과를 얻을 수 있다. 당뇨병 환자는 혈당저하의 효과측면에서는 모든 숲이 효과적이나 특히, 졸참나무숲에서 체류하는 것이 높은 효과를 경험할 수 있다.

한국 거주 조선족 노인이주자의 문화적응 스트레스와 건강증진 행위 관계 (Acculturation Stress and Health Promotion Behaviors of the Korean Chinese Elderly Immigrants Living in Korea)

  • 김향란;송미순
    • Perspectives in Nursing Science
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    • 제13권2호
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    • pp.70-80
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    • 2016
  • Purpose: This study examined the relationship between acculturation stress and health promotion behaviors in the Korean Chinese elderly immigrants living in Korea, focusing on the buffering effects of social support. Methods: We included 132 completed questionnaires in the analysis. The buffering effect was examined using a hierarchical regression analysis by adding interaction terms. Results: Health promotion scores were significantly higher in the group with a higher education level, lower depressive symptom scores, and higher levels of social support. However, no statistically significant differences were found in the health promotion behaviors by gender, age, spouse, job, financial stability, subjective health status, chronic disease, regular health checkups, or acculturation stress. The hierarchical regression analysis demonstrated that social support had a buffering effect on the relationship between acculturation stress and health promotion behaviors in the Korean Chinese elderly immigrants. Specifically, the relationship between the acculturation stress stemming from the difficulties in the workplace and health promotion behaviors was attenuated by social support. Conclusion: These findings indicate that social support significantly moderates the relationship between acculturation stress and health promotion behaviors in the Korean Chinese elderly immigrants living in Korea. A variety of strategies to enhance social support should be incorporated in the health promotion programs to decrease the negative effects of acculturation stress in the Korean Chinese elderly living in Korea.

직무스트레스와 사회적 지원이 병원종사자들의 조직효과성에 미치는 영향에 관한 연구 (The Effect of Job Stress and Social Support on the Organizational Effectiveness of Hospital Employees)

  • 고종욱;서영준;박하영
    • Journal of Preventive Medicine and Public Health
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    • 제29권2호
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    • pp.295-309
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    • 1996
  • The purpose of this study is to investigate the effect of job stress and social support on the organizational effectiveness of hospital employees and to examine the role of social support in the experience of job stress among the employees. Previous studies have yielded mixed results regarding the role of social support. Some studies provide supporting evidence for the buffering effect of social support, while others do not. Still others report findings about reverse buffering effects. These inconsistent findings are, in part, accounted for by methodological problems such as poor measurement, small sample size, and the existence of high multicollinearity. To examine more rigorously the role of social support in relation to the negative effects of job stress, this study was carefully designed to overcome methodolgical shortcomings found in the past research. In addition, unlike the previous studies, which were concerned mostly with health-related variables as consequences of job stress, in this study, three work-related variables (job satisfaction, organizational commitment, and intent to stay) which had close relationships with organizational effectiveness were examined as output variables. The sample used in this study consisted of 353 employees from a university hospital in the surburbs of Seoul. Data were collected with self-administered questionnaires and analyzed using canonical analysis and hierarchical regression analysis. The results of this study indicate that; (1) job stress has negative main effects on job satisfaction, organizational commitment, and intent to stay; (2) social support has positive main effects on the same three output variables, (3) social support does not moderate the harmful effects of job stress on the three outcome variables, and (4) the three-way interaction effects of (social support * job stress * gender) and of (social support * job stress * education) are not supported. The implications of these findings for the management of human resources are discussed.

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도로변 토양의 오염 특성과 Pb, Zn, Cd 및 Mn의 침출거동에 미치는 pH와 반응시간의 영향 (Characteristics of roadside soils and effects of pH and Time on their reaching behaviors of Pb, Zn, Cd and Mn)

  • 이평구
    • 자원환경지질
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    • 제32권1호
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    • pp.53-62
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    • 1999
  • The possibility of heavy metal pollution by contaminated roadside soils was studied under controlled conditions. The soil samples from roadside and those from a retention pond consisting of settling particles were characterized by the XRD analyses and the sequential extraction experiments. Characterization by sequential extraction, for roadside soil indicates elevate total concentrations of heavy metals. The leaching behavior of the samples under different pH and time conditions were also studied. Differences between both types of samples result mainly from the buffering effect of carbonates, present in roadside soils and lacking from settling particles. Acid leaching of the settling particles is equivalent to the sum of FI+FII+FIII, while the amounts leached from roadside soil are lower probably from kinetic reasons. The buffering effects of carbonates were found to greatly delay the onset of the leaching reactions and the extent of dissolution in most metals except for Ca and Mn. The study of leaching kinetics at pH of 6.5 and 5 showed that Cd and Zn reached the maximum possible concentration within 3 days, while Pb did not show any sign of dissolution at both ph values. The absolute amounts of dissolved Cd and Zn increased by 7 to 9 times by decreasing the pH from 6.5 to 5, indicating slightly acidified rain may result in significant metal dissolution. As deduced from both sequential extraction and leaching experiments, the relative mobility of heavy metals is found to be : Mn=Cd>Zn>>Pb>Fe, in spite of large differences in heavy metal contents and localizations.

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Lactobacillus reuteri 함유 Probiotics가 구강미생물의 생존 및 biofilm 형성에 미치는 영향 (The effects of Lactobacillus reuteri-containing probiotics on the viability and biofilm formation of oral microorganisms)

  • 이수빈;이경희
    • 한국치위생학회지
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    • 제20권3호
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    • pp.387-397
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    • 2020
  • Objectives: This study aimed to evaluate the inhibitory effects of probiotics containing Lactobacillus reuteri on Streptococcus mutans and Aggregatibacter actinomycetemcomitans. In addition, the degree of biofilm formation, initial acidity, buffering ability, and acid production performance were measured to confirm the dental caries-inducing ability. Methods: S. mutans (KCTC3065) and A. actinomycetemcomitans (KCTC2581) were used as experimental strains. The number of viable cells, degree of biofilm formation, initial pH, buffering capacity, and production performance were measured for comparing L. reuteri-containing probiotics and Bulgaris. Results: The viability of S. mutans in the groups was reduced in the following order: Bulgaris, probiotics, control. The degree of biofilm formation was significantly higher at 0% and gradually reduced at different concentrations (p<0.01). At 2.5%, the absorbance of the probiotics and Bulgaris groups differed significantly (p<0.01). The acid formation ability differed significantly based on the performance of S. mutans in each product (p<0.05). The absorbance of the probiotics group was significantly lower than that of the Bulgaris group (p<0.01). Conclusions: This study suggests that the use of L. reuteri-containing probiotics as an adjuvant for the prevention and decreasing of oral diseases may reduce their incidence, which can be considered one of the benefits of using probiotics.

Anti-Oral Microbial Effect of Ethanol Extract of Angelica gigas Nakai

  • Soon-Jeong Jeong
    • 치위생과학회지
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    • 제24권1호
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    • pp.54-61
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    • 2024
  • Background: The Korean name for Angelica gigas Nakai (AGN) is Cham-dang-gui, which grows naturally or is cultivated, and its dried roots are used in traditional herbal medicines. The AGN root exert various pharmacological effects. Despite the various pharmacological effects of the AGN root, there are no reports on its anti-oral microbial effects. The purpose of this study was to reveal the anti-oral microbial effect and the microbial and biochemical changes in oral microorganisms according to the concentration of the ethanol extract of AGN (EAGN) root, and to confirm the possibility of using EAGN as a plant-derived functional substance for controlling oral infectious microorganisms. Methods: Disk diffusion test, growth measurement, biofilm formation assay, and measurements of acid production and buffering capacity were performed to confirm the antibacterial effect of EAGN. Results: EAGN showed anti-oral bacterial effects against Streptococcus mutans and Aggregatibacter actinomycetemcomitans at all concentrations, with S. mutans showing a more susceptible effect at concentrations above 5.0 mg/ml and A. actinomycetemcomitans at 3.75 mg/ml. EAGN treatment significantly reduced A. actinomycetemcomitans growth at all concentrations tested. Biofilm formation was significantly reduced at concentrations above 3.75 mg/ml for S. mutans and 2.5 mg/ml for A. actinomycetemcomitans. Acid production in S. mutans and A. actinomycetemcomitans was significantly increased by treatment with EAGN, and the buffering capacities of S. mutans and A. actinomycetemcomitans increased from an EAGN concentration of 3.75 mg/ml and above. Conclusion: EAGN showed anti-oral bacterial effects against both S. mutans and A. actinomycetemcomitans at concentrations above 3.75 mg/ml, which were thought to be related to the inhibition of their growth and biofilm formation. Therefore, EAGN can be used as a safe functional substance derived from medicinal plants owing to its antibacterial effects against S. mutans and A. actinomycetemcomitans.